Fluids mixing and proportioning device

ABSTRACT

A fluids proportioning and dispensing device of a piston-type has a first piston that operates in a piston chamber to draw one of the fluids into the chamber and to thereafter dispense a proportioned mixture of the one fluid with another fluid. The second fluid is fed to the chamber by a pumping mechanism that has a reciprocating pump element which extends into the chamber and also into a bore in the piston housed therein. The second fluid is discharged into this piston bore and the piston carries a toggle-type valve that controls the release of the pumped fluid from the piston bore to the free space in the chamber in a manner such that the piston is moved during its fluid intake stroke by a fluid coupling that is established between the pump element and piston. The pump element is driven through a clutch drive arrangement and the device has a locking mechanism that alternately locks the pumping element in an extended position while the clutch slips and the piston is driven by a spring during its fluid discharge stroke, and then locks a discharge valve in a closed position where it remains during reciprocating movement of the pump element. A bellow-type locking mechanism is also used to interlock the pump element and the piston when a pressure drops develops in the piston chamber for reasons of an exhausted fluid supply and other valving combinations are disclosed. The device is designed to cease dispensing the fluids mixture when the supply of either fluid becomes exhausted.

ilited States Patent 1 [111 ,86 Brown 1 Sept. 30, 1975 FLUIDS MIXING AND PROPORTIONING the one fluid with another fluid. The second fluid is DEVICE [76] Inventor: Merritt J. Brown, 813 Hastings Dr.,

Kissimmee, Fla. 32741 22 Filed: Feb. 4, 1974 [21] Appl. No.: 439,580

[52] 11.5. C1. 222/135; 222/145; 222/341 [51] Int. C1. B67D 5/40 [58] Field of Search 222/1292, 135, 145, 335,

[56] References Cited UNITED STATES PATENTS 2,736,466 2/1956 Rodth 222/1292 X Primary Examiner-Stanley H. Tollberg Assistant E.\'aminer-Larry H. Martin Attorney, Agent, or Firm-Roger L. Martin, Esq.

[57] ABSTRACT A fluids proportioning and dispensing device of a piston-type has a first piston that operates in a piston chamber to draw one of the fluids into the chamber and to thereafter dispense a proportioned mixture of fed to the chamber by a pumping mechanism that has a reciprocating pump element which extends into the chamber and also into a bore in the piston housed therein. The second fluid is discharged into this piston bore and the piston carries a toggle-type valve that controls the release of the pumped fluid from the piston bore to the free space in the chamber in a manner such that the piston is moved during its fluid intake stroke by a fluid coupling that is established between the pump element and piston. The pump element is driven through a clutch drive arrangement and the device has a locking mechanism that alternately locks the pumping element in an extended position while the clutch slips and the piston is driven by a spring during its fluid discharge stroke, and then locks a discharge valve in a closed position where it remains during reciprocating movement of the pump element. A bellow-type locking mechanism is also used to inter lock the pump element and the piston when a pressure drops develops in the piston chamber for reasons of an exhausted fluid supply and other valving combinations are disclosed. The device is designed to cease dispens ing the fluids mixture when the supply of either fluid becomes exhausted.

7 Claims, 7 Drawing Figures US. Patent Sept. 30,1975 Sheet] of4 3,908,866

lillllll Sept. 30,1975 Sheet 2 of 4 3,908,866

US. Patent Sept. 30,1975 Sheet 3 of4 3,908,866

FIG. 3

US. Patant Sept. 30,1975 Sheet40f4 3,908,866

FIG. 4

1 FLUIDS MIXING AND PROPORTIONING DEVICE This invention relates to an improvedfluids mixing and proportioning device which isdesighed to mix -fluids in predetermined proportions and to'thereafter dis'-' pense the mixture. ii

Devices for'mixing fluids in predetermin'ed 'pr'opon tions and which'involv'e't'he use of a piston that operates in a piston chamber are known. Such devices rely on the piston displacement during its reciprocating movement to take in a predetermined amount of fluid and to thereafter dispense the fluid to a mixingcha'mher or pipe in'which it is mixed with another fluid that is similarly measured in another piston chamberpThe piston drive arran'g'ement'for the two fluid easuring chambers in such cases is usually mechanically coupled so that the piston movements are synchronized. In some of the prior art situations, a single piston'is involved in measuring and dispensing the two fluids for the mixture and in suc'hsituations the fluids are measured and dispensed at the opposite ends of the piston chamber. i

There are various problems which are'residentinthe prior'art devices. Among those frequently encountered are those which develop'because the devices operate in reliance on positive fluid intake pressures and/or the maintenance of predetermined pressure rangesat the outlets for the proportioned mixture. When the supply of one of the fluids is exhausted and the inlet pressure drops, the other fluid continues to be dispensed to the mixing area because of the common drive arrangement. This, of course, is'undesirable urilessimmediately detected so that thep'roport ioning'device canbe shut down. Devices'for detecting such situations to shut down the operation'of the piston drive mechanisms are known but such devices are expensive and are subject the device. In many of the prior art devicesthis situa-- tion causes a valve to open so that fluid is admitted to the chamber during the discharge stroke of the piston and hence the amount of fluid discharged'i'i'om the pis' ton chamber exceeds that contemplated bythe piston displacement.

A general object of the invention is to provide an improved fluids mixing and proportioning deviceqOne particular object of the invention'is to provide a piston type fluid mixingand proportioning device which'automatically ceases to dispense the mixture when one or more of the fluid supplies is exhausted. Yet another object of the invention is to provide an improved device which fulfills the prior objective witho'ut'the 'need' for inactivating the piston drive mechanism. Still a further object is to provide an improved piston-type mixing and proportioning device which can be used to dis- .p'ense the mixture against either a positive-or a negative pressure head at the mixed fluid outlet of the device. Still a further object of the invention isto provide an improved device'of the kind contemplated and which avoids the use of a conventional piston'rod-type mechanical coupling withthe piston for purposes of'i'mparting reciprocating motion to the piston. Yet another "object isto provide areliable liquids proportioning device that avoids the need for complicated and expensive auxiliarye'quipment for detecting an exhausted supply of thefluids being mixed.

' In accord with the'invention provisions are made for i rneasuringone fluid by means of a piston that isdisplaced d uring itsintake strokeby means that involves the establishment of a fluid drive coupling between the piston and a; reciprocating element that is used in pumping the second fluid into the piston'chamber. The

fluidinvolved in the establishment ofthe drive coupling is deriv'ed through the operation of the pumping mechanismand provisions are made during the discharge stroke of the piston for mixing fluid us d in establishing lthe conpling with that drawn into the chamber during the intake stroke of the piston. Certain a spects of the inve ntionihave to do with certain valvingarrangements and'locking mechanisms which permit the device to discharge ag a insta negative: pressure head and to also The novel features which are believed to be characvteristic of this invention are set forth with particularity irithe appended claims. The invention, itself, however, both as to its organization and. method of operation, to-

gether with further objects and advantages thereof,

may best be understood by reference to the following ..description takeninconnection the accompanying drawings, and in which:

. 7 FIG. 1 is a vertical section taken generally alongthe vertical axis of the deviceat the commencement of the intake stroke of the piston; I ,FIG. 2 is a vertical section similar to FIG. 1 and shows the components of the device as the piston is advancing during the intake stroke; FIG. 3 is a vertical section similar to FIGS. 1 and 2 showingthe components'of the device the commencement of the fluid discharge stroke of the piston; FIG; 4 is-a vertical section similar to FIGS. 1 through 3 and shows the componentsof the device at an advanced stage during the fluid discharge stroke;

.FIG. 5 isa horizontal view of'afragment of,the pumping mechanism as generallyseen along the Lines 55 of FIG. 1;

FIG. 6 is a horizontal section view through the'piston as'generally seen along the Lines 6+6 of FIG. 1; and

FIG. 7 is a horizontal view through a fragment of the piston as generally seen along the Lines 77 of FIG. 1. i

Reference is made to the drawings and'to the device embodying the principles of the invention shown therein. The device it) is" illustrated in an arrangement for mixing gasoline and lubricating oil that is then dispensed for use as the fuel and lubricant in a two cycle engine.

- Device 10 includes a body portion 11 that has an inlet passageway 12 for the gasoline, a compartment 13 for receiving the lubricating oil, and an outlet passagecompression spring 17. During the fluid intake stroke,

the piston 16 is driven by means that includes a fluid drive eoupling which is established in a center bore 18 of the piston 16 from fluid that is discharged from a mechanism 19 for pumping the oil from the compartment 13 to the piston chamber 15.

The body portion 11 (see FIG. 1) includes a cylindrical metal base component 21 and a hollow, cylindrical metal piston casing 22. The latter is equipped at one end with an annular flange 23, and the two body components 21 and 22 are sealed in the assembled device by means of an O-ring 24 that is interposed between the flange 23 and upper end of component 21 and clamped in place by threaded metal fasteners 25.

The oil compartment 13 is formed by three bores in the base component 21 and which are evident in the drawings. The lower end of the base component 21 has a bottom covering metal disk component 26. This disk 26 is fixed to the base component 21 by metal fasteners, not shown, but which serve to clamp an O-ring 27 in place to provide a fluid-tight seal for the compartment area. The lubricating oil in the illustration is fed to compartment 13 by a gravity feed pipe 29 that is threaded in the base component 21 at the inlet port 30 for the compartment and is connected to a suitable oil supply source that is stored under atmospheric pressure conditions.

The gasoline is fed to the fluid inlet passageway 12 from a suitable atmospheric supply source by means of a gravity feed pipe 31 that is threaded in the base 21 at the inlet port 32 for passageway 12. The outlet port 33 for passageway 12 communicates with the fluid tight end 34 of chamber 15 through an interior end wall 35 which serves to define this end of the chamber. The inlet passageway 12 is equipped with a valve chamber 36, and here the device is provided with a check valve mechanism 37 that normally serves to check fluid flow from the outlet port 33 to the inlet port 32 of the passageway.

The check valve mechanism 37 includes a valve 38 that operates between an open position 39 and a closed position 40 relative to a tapered seat 41 at the inlet port 32. The valve 38 is fixed to a shaft 42 that extends through a body bore 43 and into compartment 13. Here the shaft carries a tapered head component 44 which is arranged for cooperation with a protuberance 45 that is carried on a yoke component of the pumping mechanism so as to maintain the valve mechanism 37 in its closed position 40 during the fluid discharge stroke of piston 16 as will be subsequently seen. When thus maintained in the closed position, the valve serves to check the flow of gasoline in both directions in the inlet passageway 12. Mechanism 37 also includes a coiled compression spring 46 that surrounds the shaft 42 in chamber 36 and constantly biases the valve 38 toward its closed position 40. I

The outlet passageway 14 for the mixed fluids is formed by a bore 49 in the base component 21. This bore 49 opens into the chamber through end wall 35 to provide an inlet port 54 for receiving the fluids that are discharged from the device through the outlet passageway 14. Bore 49 also serves as a valve chamber 51 for a valve mechanism 52 that operates to open and close the outlet port 53 of passageway 14. Here in the outlet 53, the device has a check valve 164 which includes a ball 165 that is urged by a spring 166 to a closed position so as to check fluid flow back into the piston chamher if a reduced pressure condition develops in the chamber. Here in the outlet 53 the device is also threadingly connected to a discharge pipe 54 for receiving the mixed fluids.

Bore 49 has an axis 55 which is parallel to the line of piston movement along the axis 56 of casing 22. Mechanism 52 has an open ended hollow, cylindrical element 57 that is coaxially arranged in bore 49. This element 57 is axially movable in the bore 49 and the lower end 58 functions as a valve that moves with the element between a closed position 59 at which the outlet port of passageway 14 is closed and an open position 60 (see FIG. 3). At the base of the bore 49 the valve mechanism is equipped with a coiled compression spring 61 that operates against the valve end 58 and constantly urges the element toward the open position 60.

The upper end 62 of element 57 has an annular peripheral groove or recess 63 for receiving a ball detent 64 of a releasable locking mechanism 65 that performs a duo function in the operation of the device. For one, mechanism 65 serves to lock the valve in the closed position 59 during the fluid intake stroke of piston 16 and also during the extension and retraction of a pistontype element 66 of the pumping mechanism 19. The other function of the locking mechanism 65, is to lock the piston-type element 66 at its extended position 67 during the fluid discharge stroke of piston 16. The action of the locking mechanism is such that when the pumping element 66 is locked at its extended position the element 57 is free to move upwardly under the influence of spring 61 and when the element 57 is locked in its closed position, the pumping element 66 is released and free to retract. As such, during the discharge stroke of the piston 16, the outlet passageway 14 remains open under the influence of spring 61 so as to receive the fluids displaced in the chamber by the downward movement of the piston and to pass the fluids to the outlet port 53 via the open ended hollow passageway 70 in the element 57. Element 57 is arranged at the open position 60 for the valve to be engaged by piston 16 as it moves into its lower position 68. The valve is accordingly closed in response to the movement of the piston into its lower position 68. The element 57 is provided with radially extending ports 73 in its upper end 62. These ports communicate with the peripheral area in the recess 63 and with the internal passageway 70 through the element so as to facilitate fluid movement from the space 71 between the lower end face 72 of piston 16 and the wall 35 as the piston reaches its lower position 68 in the operating cycle.

Piston 16 includes a cylindrical body member 74 that is sealed in the casing at its perimeter by a pair of 0- rings 75 that serve to prevent the passage of fluid between the opposite ends 34 and 76 of thechamber. Member 74 has a center bore 18 with an axis 77 that is arranged in coaxial alignment with the axis 56 of chamber 15. Member 74 also has another bore 78 which is radially offset from the center bore 18 and arranged in coaxial alignment with the bore 49 in the base component of the body 11. The top of the piston body member 74 is equipped with a cylindrical disk 79 that is fixed to the member 74 so as to close the upper ends of bores 18 and 78. This disk 79 has a surface recess 80 which interconnects the closed ends of these bores and provides at the closed end 81 of bore 18 an inlet port 82 for the fluid passageway 83 that is provided in the piston by bore 78.

Bore 78 also serves as a chamber for the valve 86 of I a toggle-type valve mechanism 87. Mechanism 87 includes an elongated, open ended, hollow cylindrical element 88 which at the valve end 86 of the element is sealed in the offset bore. 78 by means of an O-ring 89. The element 88 is coaxially arranged and linearly movable in the offset bore 78, and the upper end 86 of the element serves as the valve component of the mechanism. Element 88 is movable between an open position '90 (see FIG. 4) and a closed position 91 (see FIG. 1)

relative to the inlet port 82 of passageway 83 and it has a pair of spaced annular peripheral grooves 92 and 93 for receiving a ball detent 94 of a mechanism 95 for retaining the valve at its open and closed position during the automatic operation of the device.

The lower end of element 88 is integral with the valve component end 86 in the illustrated embodiment and takes on the form of an elongated, hollow cylindrical section 97 that extends through the discharge port 98 of passageway 83 and also through the inlet port 50 of passageway 14. As seen in the figures, this section 97 .also extends through the hollow passageway 70 in the sleeve element of mechanism 52 and is radially offset from the interior walls thereof so as to facilitate the flow of fluids through the hollow passageway 70. Section 97 has radially extending ports 99 which communicate with the hollow and also with the space 71 at the fluid tight end 34 of chamber so as to enable the oil and gasoline to freely mix in the chamber and in the outlet passageway during the fluid discharge stroke of piston 16.

The main function of section 97 of mechanism 87 is to sense the movement of the piston 16 as it moves into its lower bottom dead center position 68 adjacent to the end wall 35 and in response to such movement to move the valve component end 86 of the element into its closed passageway position 91. This is accomplished by providing a stop 100 at the lower end of bore 49 and which is encountered by the lower end of the element 88 as the piston 16 moves into its lower position 68. This stop 100 comprises a small, cylindrical metal element that is threaded in the body base component at the closed end of the outlet bore. Spring component 61 of mechanism 52 as seen in the drawings is coiled around this stop element. As piston 16 moves into its lower position 68, the lower end of section 97 encounters the stop 100. This forces the ball detent 94 of mechanism 95 out of the annular recess 92 against the urgings of the spring component 101 of the mechanism and, as the piston moves further down into its lower position 68 to close the piston passageway, the spring 101 forces the ball detent into the other annular recess 93 so that the valve end 86 of the element is then retained in the closed position 91 in the inlet port of the passageway 83. As will be subsequently seen, this sealing off of .the passageway 83 permits the establishment of a fluid drive coupling in the center bore 18 and which is used in driving the piston to its upper position 102 during the fluid intake stroke.

Valve 86 of the toggle-type mechanism 87 is moved to the open position 90 by means of a cylindrical plunger 104. This plunger 104 fits in a cylindrical recess in the disk 79 at the upper end of the offset bore in the piston. The plunger 104 is arranged in coaxial working alignment with the axially movable element 88 of mechanism 87 and is threadingly connected to a shaft 106 that extends through a bore in the upper end face 108 of piston 16. The upper end of shaft 106 carries a head element 109 that is offset from the end face 108, and the mechanism includes a coiled compression spring 110 that is interposed between the head 109 and face 108 to constantly urge the plunger 104 into the recess area 105.

The plunger mechanism serves to sense movement of the piston 16 into its upper or top dead center position 102 and, in response to such movement, to move the valve 86 to its open position in passageway 83. This is accomplished in the illustrated embodiment through contact with an adjustable set screw 112 which is threadingly mounted in the upper end wall 113 that defines the upper end 76 of the piston chamber. The set screw 112 is arranged in working alignment with the head element 119 and as the piston 16 moves into its upper position 102 during the fluid intake stroke, the head encounters the lower end of the screw 1 12 to stop the upward movement of the plunger. This, of course, stops the upward movement of the valve element 88 that is carried by the piston 16 and, as such, further upward movement of piston 16 into its upper position forces the plunger down relative to the piston 16 and shoves the element 88 into the open position 90. As this happens, of course, the ball detent 94 of retaining mechanism is forced out of recess 93 against the urgings of spring 101 so that. at the end of the intake stroke, the detent 94 is forced by the spring into the other recess 92 to thereafter maintain the valve in an open position during the fluid discharge stroke of the piston 16.

The valve end or section 86 of element 88 has an enlarged opening 114 in which the lower end 115 of plunger 104 is received when the valve is in the closed position 91. To facilitate movement of the plunger 104 in the cap recess from its position shown in FIG. 1 to its position shown in FIG. 3, the plunger has an orifice 116 that communicates with the piston passageway through the element. This orifice permits the flow of fluid into the recessed space as the plunger 104 moves the valve to its open position. The disk 79 also has a small orifice 117 that communicates with the recess and inlet port end of the piston passageway. This orifice permits fluids to flow from the inlet port to the recessed space when the piston reaches top dead center so as to relieve the pressure in the center bore and permit the spring to thereafter urge the plunger 104 back into the recess area to fully open the piston passageway at the end of the fluid intake stroke. Orifice 117 thus permits the oil to initially bleed out of the center bore 16 and ultimately into the discharge passageway through orifice 116 as the piston 16 reaches top dead center and facilitates the return of the plunger to the recess and hence the complete opening of the passageway.

The pumping mechanism 19 for pumping the oil into the piston chamber 15 comprises an elongated, cylindrical element 66 which is sealed at its perimeter in a body bore 121 by means of an O-ring 120. As thus mounted in the body bore, the element 66 is mounted for reciprocating linear movement along the line of movement of the piston 16 between an extended position 67 and a retracted position 123. The element 66 has a passageway 124 that extends between and opens at its opposite ends into the oil compartment 13 and piston chamber 15. The body bore 121 is arranged in the base component 21 of body 1 l in coaxial alignment with the center bore 18 in piston 16, and the element 66 extends through the bore 121 in an arrangement such that its lower end portion 125 is disposed in the oil compartment while the opposite end portion 126 is located in the center bore 18 of piston 16. This end portion 126 functions as a piston in cent r bore 18 and is equipped with a peripheral seal shown in (in; form of an O-ring 118.

' At the upper end portion 126, the element passageway'124 is enlarged to form a chamber for a ball valve component 129 of a check valve mechanism 130 that ter bore of the piston'during the operation of the pumping mechanism. As is evident from the drawings, the compression spring 133 constantly urges theball 129 againstthe valve seat 135 so as to check the flow in the direction of the oil compartment. This check valve mechanism 131) cooperates with valve mechanism 87 in establishing the fluid drive connection between the pump element 66 and piston 16 during the fluid intake stroke of the piston.

The mechanism 139 for driving the pump element 66 comprises a constant torque clutch 140 that has a clutch plate. 141 which is fixed to a shaft 142 that is driven by a suitable motor, not shown. The other clutch plate 143 of clutch 140 is secured to a shaft 144 which is journaled in a bearing 145 that is mounted in a body bore designated at 146. Shaft 144 extends into the oil compartment 13 and carries a crank 147 which is rotatably driven through its shaft connection with the clutch 140.The crank is linked to the pump element ,66 by an arm 148. Thelower end of arm 148 is pivotally connected to the crank 147 by a pivot pm 149, and the other end of the crank is disposed between the arms 150 of a yoke 151 where it is connected to the yoke by means of a pm 152. The upper end of yoke 151 fits in .an end socket of the pump element 66, and here the yoke 151 is fixed in place by another pin 154. Above the socket, the pump element 66 is provided with radially extending openings that serve as the inlet ports for the passageway.

Mechanism 139 isdesigned to drive the pump element 66 between its. extended and retracted positions 67 and 123 as seen in FI S. 1 and 3. At the retracted position 123, the discharge end portion 126 of element 66 is located adjacent to the end wall 35. At the extended position, this end portion 126 is offset from the wall 35 toward the other interior end wall 113 that is located at the opposite end of the piston chamber. As element 66 moves from its retracted position to its extended position, the check valve carried by the element is closed and a fluid drive connection is established between piston 16 and the pump element 66. On the other hand, when the element moves from its extended position to its retracted position, the valve carried by the element opens to admit oil into the center bore of the piston.

The device also has a mechanism 170 which is designed to lockthe piston at an intermediate position between its extended position 67 and retracted position 123 when the pressure in the chamber falls to atmospheric for reasons that the supply of gasoline becomes exhausted.

" This mechanism 170 is mounted in a bore 171 that opens through the lower end face 72 of the piston 16. Bore 171 is radially offset from and parallel to the center bore 16 and it houses a bellows 178 which operates between the closed end 172 of the bore 171 and a metal disk 173 that is axially slidable in the enlarged lower end 174 of the bore. The disk 173 has an annular cam surface 175 at its lower end that operates against the end ofa radially extending pin 176 which is housed in a radially extending bore 177 that opens at its opposite end into bores 171 and 18.

The pressure in the bellows 178 is slightly above atmospheric under ambient surrounding conditions so that it expands when the pressure in the piston chamber falls to atmospheric or therebelovv and urges the disk 173 downwardly. This causes the cam surface 175 to bear against the end of pin 176 and tends to force the pin 176 toward the pump element 66 in bore 18. Element 66 has an annular recess 179 at its upper end and which is designed to receive the pin 176 and cooperate therewith in locking the piston 16 to element 66 under certain circumstances, as will be subsequently seen.

-Whe'n the pressure conditions in the working end of the chamber exceed that in the bellows 178, the disk is thrust upward against the shoulder 180 and this permits the pin 176 to assume a disengaged position with respect to the element 66.

The operation of the device 10 is best understood by the operating cycle depicted in FIGS. 1 through 4. In FIG. 1, the components of the device 10 are seen at the commencement of the cycle and at which point the pump element 66 is in its retracted position 123 and the piston 16 is at its lower position 68 adjacent to end wall 35; Under such circumstances, the piston 16 having engaged the upper end 62 of element 57 and forced the valve section 58 to a closed position 59 in passageway 14 as the piston moved into the lower position, the element 57 is locked in place by means of the ball detent 64 of mechanism 65. The other ball 157 of the mecha- FIG. 1 and caused the lower end 96 of element 88 to encounter the stop and force the valve 86 into its closed passageway position seen therein.

The ball 129 of the check valve mechanism that is carried by the pump element is in a closed position in the passageway 124 at the commencement of the cycle. As such and with the valve 86 of the toggle valve mechanism 87 in a closed position, the oil is trapped in the piston center bore 18 to provide the the fluid drive linkage between the pump element 66 and piston 16. Thus, as the pump element 66 reached its retracted position 123 to commence the cycle, the check valve 130 closes and a fluid drive coupling is established in the center bore of the piston through cooperation with the toggle valve mechanism. Accordingly, as the element 66 is driven upwards toward its extended position 67 as depicted in FIG. 2, the piston 16 is driven towards its upper position 102 by virtue of the fluid drive connection established in bore 18. Such upward movement of course draws gasoline through the inlet passageway 12 and forces the check valve 38 of mechanism 37 to its drive the pin 176 toward the pump element 66. However, the latch end 181 of the pin merely presses against the periphery of the element 66 during th e intake stroke. A I l I Several things transpire as the pump element 66; enters its extended position 67 at the end of the fluid intake stroke of piston 16. For one, as the piston 16 enters its upper position 102 at the end of the intake stroke, valve 38 of mechanism 37 seats 'itself to' close the intake passageway 12. To in'sure that the va'lve mechanism,37 remains closed during the subsequent discharge stroke of piston 16,the yoke is equipped with a lateral protuberance 'that aligns itself with the head component 44 to thus prevent the valve from opening in the event a negative pressure develops at'the discharge port of the discharge passageway This condition exits as long as the pumping element remains at its extended position.

The pump element 66 is equipped Rwi ihan annular,

peripheral recess 160 at itslower end and as'th'e pumping element 66 reaches its extended position 12"2,"this recess 160 becomes aligned with the bore 161 for the balls 157 and 64 ofrnechanism 65. When this happens, the upper force that is exerted by spring 6 1 on element 57 of mechanism 52 forces the Cletent balls and 64 to ,the left as seen in FIG. ,3. This releases the valve element 57 in the diseharge passageway and element :57 accordingly moves under the influence of'spring 61 to a an open position so that the fluids in the space between the lower face and end wall 35 thereafter discharge from the device-throughthe outlet passageway 14.;Sim ultaneously, withthe release of element 57 ball157 v is forced in to a locking position therecess 160jof pump element 66 so that reciprocating movementof the pump eiern ent ceases until such time as the valve in the passageway is again closed. l

The third thing that happens as the pump element 66 and piston16 enter the position shown in FIG. 3 is that the toggle valve mechanism 87 is forced to its open po- "-sition 90 in the piston passageway. Thus the head' 109 '.of the plunger mechanism encounters the set screw 1 l2 and forces the valve to the open position where it is re- -tained during the subsequent fluid dischar'ge stroke by the ball detent 94 in groove 92. Once'the piston passageway 83 is opened, the fluid drive connection between piston 16 and pump element 66 is broken a nd the piston l6 is thereafter urged toward the lower end wall 35 under the driving influence .of spring 17. This commences the fluid discharge stroke of piston 1 6 so that the fluids in the space between the pistonand end wall 35 are forced outthrough the discharge passageway while simultaneously the oil, in bore 1 8 is forced out through .the piston passageway to mix with the gasroline in the space between the piston and end wall and 6 in the discharge, passageway area. a l V t t v When the spring 17 starts its piston 16 drive function the pressure at the intake end of the chamberinc'rea'ses 1i) aridthis causes the b'ellows 17s tocollapse and-'the disk "173ioassurne a position against the shoulder 80. This r ele'aves the forces on pin 17650 that as the piston 16 'i'etui'ns to its bottom position the pin fails tolockingly 5 jengage the'recess'179 in the pumpelement.

' Throughout this discharge stroke of piston 16, pump element" 66'is locked in'its extended position 67- bythe ball detent 157 of locking mechanism so that the clutch component of the drive mechanism 139 10 continues to slip throughout the discharge stroke of the piston. Thereafter, as the piston 16 approaches its lower position 68'; the upper end 62 of element 57 is encountered by the lower face of the piston and the element57 in theoutlet passageway 14 is forced to rel5 spond to the piston movement at theend .of the discharge'stroke and to assume the closed position 59. As the outlet passageway: isbeing closed, the lower endtof the cylindrical section 97.0f the toggle valye mechanism 87 encounters the stop 100. Consequently, in re 20 sponse to the movement of the piston into its lower position, the valve formingend 86 of the element 88 is moved to itsclosed position 91in ,the piston passageway. As the piston moves into its lower positionand element 57 is forced to its closed position, the :pumpelement 66 is released by the locking mechanism. Thusas element 57, moves into the closed position 59, the groove, 63 in the upper ,end. of the element becomes aligned with the bore for the detent balls and the ,downward force being applied to the pump element 66 Q -by,the drive mechanism forces the detent balls to the right as viewed in FIG. 4. This releases pump element 66 andlocks the valve element 57 in a closed position 5,9.until;the pump element again reaches the ex- 1 tendedposition. with the release of the pump element 35 66, the, clutch ceasesto, slip and the driverne'chanism 139 is. free to drive the pump element to its retracted position at which the cycle repeats itself." During this retraction the piston passageway is closed by the toggle V valve mechanism and hence the check valve carried by 9, the pump element 66 opens; and admits oil into the cenfl ter bore of the piston and in an amount which, of course, is determined by the space displacement inivolve d in the retracting movement of the element 66 in the piston center bore. i I l Among the advantagesinvolved in the use of the device is the fact that it ceases to discharge a fluid if the supply source of either fluid becomesexhausted. For example, if the oil source becomes exhausted and air is admitted to the oil compartment, air will be admitted to the piston center boreduring its retraction. Thereafter howe ver andduring its extension, the air in the bore will be simply compressed. l

I The pressure" developedhowever is insufficient to overcome theurgings of spring17 and hence the piston 16 remains at its lower position and the valve in the outlet passage remains closed so thatelem'ent 66 reciprocates but fails to establish the needed fluid drive connection to 'cause movement of the piston 16.

When the gasoline supply becomes exhausted, air is admitted 'to the working end of the piston chamber during the'intake stroke'of the piston 16. However, the pressure conditions in the chamber at the end of the piston 16 intake stroke are below that in the bellows "178'Q'Consequently; as the piston 16 is urgedback towar dits lower position by spring 17, the bellows 178 of mechanism is urging the disk downwardly and hence also urging the pin 176 toward the pump element. As such, when the piston 16 reaches a position at which the pin 176 becomes aligned with the recess 179, it enters the recess and locks the piston 16 to the pump element 66. Since the pump element 66 is locked in its extended position during the discharge stroke of piston 16, piston 16 merely hangs up and the clutch continues to slip until the situation is remedied. The check valve 164 in the discharge port serves under such circumstances to prevent back flow of fluid when the device is operating against a positive discharge pressure and which could otherwise relieve the reduced pressure condition that serves to lock the piston elements together.

While only certain preferred embodiments of this invention have been shown and described by way of illus tration, many modifications will occur to those skilled in the art and it is, therefore, desired that it be understood that it is intended herein to cover all such modifications as fall within the true spirit and scope of this invention.

What is claimed as new and what it is desired to secure by letters Patent of the United States is:

l. A fluids proportioning and mixing device comprising a body portion having a piston chamber with opposite ends, a passageway connected to a source of first fluid and having a discharge port at one of said ends of said chamber, a compartment connected to a source of second fluid, and an outlet passageway connected to the chamber at said one end, a piston located in the chamber and linearly movable between a first position at said one end and a second position spacedly offset and more remote from said one end, said piston having an end face which confronts the space between the piston and said one end, a bore which has an axis parallel with the line of movement of the piston, an opening at said end face, and a closed end offset from said end face, and a piston passageway communicating with the space and with the closed end of said bore, means for pumping the second fluid from the source therefor to said bore comprising an elongated passageway containing element having a fluid outlet end located in said bore anda fluid inlet end located in said compartment, said element being mounted in the body portion in coaxial alignment with said bore and reciprocatingly movable along its longitudinal axis between a retracted position at which said fluid outlet end is located adjacent to said one end and an extended position at which said fluid outlet end is spacedly offset and more remote from said one end, said pumping means comprising first valve means carried by said element for checking fluid flow from the outlet end to the inlet end of the element, said device comprising means for urging the piston from its second position to its first position, second valve means carried by said piston and being responsive to piston movement at its first position to close said piston passageway and responsive to piston movement at its second position to open said piston passageway, said pumping means comprising driven means connected to said element for advancing the element from its retracted position to its extended position, and said first valve means and said second valve means being cooperatively associated to maintain a fluid drive connection between the element and piston during such advancing of the element to thereby advance said piston from its first position to its second position against the urgings of said urging means.

2. A fluids mixing and dispensing device in accord with claim 1 where the passageway connected to the first fluid source has a fluid inlet port connected to said first fluid source, and where the device comprises check valve means for checking fluid flow from the outlet port to the inlet port of the passageway connected to said first fluid source.

3. A fluids mixing and dispensing device in accord with claim 1 where the passageway connected to the first fluid source has a fluid inlet port connected to said first fluid source, and where the device comprises means operating to check fluid flow between the inlet port and outlet port of the passageway connected to said first fluid source when said element is at its extended position. i

4. A fluids mixing and dispensing device in accord with claim 1 where the device comprises means operating automatically to releasably lock the elongated element at its extended position until said urging means urges the piston into its first position and being releasable in response to the piston movement at its first position, where the passageway connected to the first fluid source has a fluid inlet port connected to said first fluid source, and where the device comprises means operating to check fluid flow between the inlet port and outlet port of the passageway connected to said first fluid source when said element is locked at its extended position.

5. A fluids mixing and dispensing device in accord with claim 1 where the device comprises third valve means responsive to movement of said piston at its first position to close said outlet passageway and responsive to movement of said element at its extended position to open said outlet passageway, means operating automatically to releasably lock the elongated element at its extended position and being releasable in response to movement of said piston at its first position which is transmitted by said third valve means.

6. A fluids mixing and proportioning device comprising a body portion having interior walls that are spaced apart and define the opposite ends of a piston chamber therebetween, a first passageway for delivering a first fluid to the chamber which has a discharge port located in one of said walls and an inlet port, a compartment having an inlet port for receiving'a second fluid therein, a second passageway for delivering a mixture of the first and second fluids to the exterior of the device which has an inlet port located in said one wall, a piston located in the chamber and linearly movable between a first position which is spacedly offset from said one wall, means urging the piston toward said one wall, and means for pumping the second fluid from the compartment to the chamber; said piston having opposite end faces which include one end face that faces said one wall, a bore which has an axis arranged in parallel with the line of movement of the piston, an end opening in said one end face, and a closed end that is offset from said one end face toward the other of said opposite end faces, and a third passageway which communicates with the bore at said closed end and with the exterior of the piston at said one end face thereof, said pumping means comprising elongated means extending between the compartment and chamber in coaxial alignment with the axis of the bore and having opposite end portions respectively located in said compartment and in said bore of the piston, said elongated means having a fourth passageway for conveying the second fluid from the compartment to the bore of said piston which has an inlet port in the one of the opposite ehd portions that is located in the chamber and a discharge port in the other of the opposite end portions, said elongated means being mounted in the body portion for reciprocating longitudinal movement between a retracted position at which said other end portion is located adjacent said one wall and an extended position at which said other end portion is located at a position that is offset from said one wall toward the other of said walls, said bore being arranged when the piston is at its first position to therein accommodate movement of said other end portion between the locations therefor at the retracted and extended positions of the elongated means, said pumping means comprising first valve means carried by said elongated means for checking fluid flow in the fourth passageway from the discharge port to the inlet port thereof, and driven means connected to said elongated means for driving said elongated means between its extended and retracted positions, said device comprising second valve means responsive to movement of the piston at its first position to close said second passageway and responsive to movement of the elongated means at its extended position to open said second passageway, third valve means carried by said piston and responsive to movement of the piston at its first position to close said third passageway and responsive to movement of the piston at its second position to open said third passageway. fourth valve means for checking fluid flow in the first passageway from the discharge port to the inlet port thereof, means for releasably locking the elongated means at its extending position and being releasable in response to piston movement at its first position, and means for driving said driven means.

7. A fluids proportioning and dispensing device comprising a piston chamber having opposite ends, a fluid inlet passageway communicating with the chamber at one of said ends for admitting a first fluid to said chamber, a fluid discharge passageway communicating with the chamber at said one end for discharging a mixture of said first fluid and a second fluid, a piston linearly movable in the chamber, elongated means linearly movable relative to said piston for pumping said second fluid into the chamber, and means for reciprocatingly driving said piston in said chamber including means for establishing a fluid drive coupling between said elongated means and said piston. 

1. A fluids proportioning and mixing device comprising a body portion having a piston chamber with opposite ends, a passageway connected to a source of first fluid and having a discharge port at one of said ends of said chamber, a compartment connected to a source of second fluid, and an outlet passageway connected to the chamber at said one end, a piston located in the chamber and linearly movable between a first position at said one end and a second position spacedly offset and more remote from said one end, said piston having an end face which confronts the space between the piston and said one end, a bore which has an axis parallel with the line of movement of the piston, an opening at said end face, and a closed end offset from said end face, and a piston passageway communicating with the space and with the closed end of said bore, means for pumping the second fluid from the source therefor to said bore comprising an elongated passageway containing element having a fluid outlet end located in said bore and a fluid inlet end located in said compartment, said element being mounted in the body portion in coaxial alignment with said bore and reciprocatingly movable along its longitudinal axis between a retracted position at which said fluid outlet end is located adjacent to said one end and an extended position at which said fluid outlet end is spacedly offset and more remote from said one end, said pumping means comprising first valve means carried by said element for checking fluid flow from the outlet end to the inlet end of the element, said device comprising means for urging the piston from its second position to its first position, second valve means carried by said piston and being responsive to piston movement at its first position to close said piston passageway and responsive to piston movement at its second position to open said piston passageway, said pumping means comprising driven means connected to said element for advancing the element from its retracted position to its extended position, and said first valve means and said second valve means being cooperatively associated to maintain a fluid drive connection between the element and piston during such advancing of the element to thereby advance said piston from its first positIon to its second position against the urgings of said urging means.
 2. A fluids mixing and dispensing device in accord with claim 1 where the passageway connected to the first fluid source has a fluid inlet port connected to said first fluid source, and where the device comprises check valve means for checking fluid flow from the outlet port to the inlet port of the passageway connected to said first fluid source.
 3. A fluids mixing and dispensing device in accord with claim 1 where the passageway connected to the first fluid source has a fluid inlet port connected to said first fluid source, and where the device comprises means operating to check fluid flow between the inlet port and outlet port of the passageway connected to said first fluid source when said element is at its extended position.
 4. A fluids mixing and dispensing device in accord with claim 1 where the device comprises means operating automatically to releasably lock the elongated element at its extended position until said urging means urges the piston into its first position and being releasable in response to the piston movement at its first position, where the passageway connected to the first fluid source has a fluid inlet port connected to said first fluid source, and where the device comprises means operating to check fluid flow between the inlet port and outlet port of the passageway connected to said first fluid source when said element is locked at its extended position.
 5. A fluids mixing and dispensing device in accord with claim 1 where the device comprises third valve means responsive to movement of said piston at its first position to close said outlet passageway and responsive to movement of said element at its extended position to open said outlet passageway, means operating automatically to releasably lock the elongated element at its extended position and being releasable in response to movement of said piston at its first position which is transmitted by said third valve means.
 6. A fluids mixing and proportioning device comprising a body portion having interior walls that are spaced apart and define the opposite ends of a piston chamber therebetween, a first passageway for delivering a first fluid to the chamber which has a discharge port located in one of said walls and an inlet port, a compartment having an inlet port for receiving a second fluid therein, a second passageway for delivering a mixture of the first and second fluids to the exterior of the device which has an inlet port located in said one wall, a piston located in the chamber and linearly movable between a first position which is spacedly offset from said one wall, means urging the piston toward said one wall, and means for pumping the second fluid from the compartment to the chamber; said piston having opposite end faces which include one end face that faces said one wall, a bore which has an axis arranged in parallel with the line of movement of the piston, an end opening in said one end face, and a closed end that is offset from said one end face toward the other of said opposite end faces, and a third passageway which communicates with the bore at said closed end and with the exterior of the piston at said one end face thereof, said pumping means comprising elongated means extending between the compartment and chamber in coaxial alignment with the axis of the bore and having opposite end portions respectively located in said compartment and in said bore of the piston, said elongated means having a fourth passageway for conveying the second fluid from the compartment to the bore of said piston which has an inlet port in the one of the opposite end portions that is located in the chamber and a discharge port in the other of the opposite end portions, said elongated means being mounted in the body portion for reciprocating longitudinal movement between a retracted position at which said other end portion is located adjacent said one wall and an extended position at which said other end portion is located At a position that is offset from said one wall toward the other of said walls, said bore being arranged when the piston is at its first position to therein accommodate movement of said other end portion between the locations therefor at the retracted and extended positions of the elongated means, said pumping means comprising first valve means carried by said elongated means for checking fluid flow in the fourth passageway from the discharge port to the inlet port thereof, and driven means connected to said elongated means for driving said elongated means between its extended and retracted positions, said device comprising second valve means responsive to movement of the piston at its first position to close said second passageway and responsive to movement of the elongated means at its extended position to open said second passageway, third valve means carried by said piston and responsive to movement of the piston at its first position to close said third passageway and responsive to movement of the piston at its second position to open said third passageway, fourth valve means for checking fluid flow in the first passageway from the discharge port to the inlet port thereof, means for releasably locking the elongated means at its extending position and being releasable in response to piston movement at its first position, and means for driving said driven means.
 7. A fluids proportioning and dispensing device comprising a piston chamber having opposite ends, a fluid inlet passageway communicating with the chamber at one of said ends for admitting a first fluid to said chamber, a fluid discharge passageway communicating with the chamber at said one end for discharging a mixture of said first fluid and a second fluid, a piston linearly movable in the chamber, elongated means linearly movable relative to said piston for pumping said second fluid into the chamber, and means for reciprocatingly driving said piston in said chamber including means for establishing a fluid drive coupling between said elongated means and said piston. 